EMPIRE STATE BUILDING, 1931
Opened in the teeth of the Depression as a mighty symbol of rebirth, the 102-floor building got off to a wobbly start financially. Built by General Motors executive John Raskob, the building reigned for 42 years as the world's tallest. Its Art Deco crown, intended as a mooring mast for blimps, served as a handy perch in King Kong. A few skyscrapers have since soared higher, but none has surpassed its limestone majesty.
THREE GORGES DAM, 2009
Mao once dreamed of taming the Yangtze, China's longest river, whose floodwaters have claimed the lives of millions. Officials expect...